BOSTON — A professor at the Massachusetts Institute of Technology announced Monday he began a hunger strike to protest the university's decision to deny him tenure.

James Sherley, who is black, said the decision was based on race.

The 49-year old scientist said he tried for two years to persuade administrators to reverse the department head's rejection of his tenure bid. The administrators deny Sherley's allegations and say fewer than half of junior faculty members are promoted to tenured positions.

Sherley works with adult stem cells and opposes research using human embryonic stem cells because he believes it amounts to taking human life. In September, he won a $2.5 million grant from the National Institutes of Health.